The xms spy is considered to be one of the best multi tools available around for xml. It knows how to deal with XSLT, XPath, XQuery, WSDL, SOAP etc.
The complete spy suite consists of the following products:
1. XMLSpy : This is a xml editor that allows the user to create, debug, validate and edit xml doucments in standard recognized way.
2. MaprForce : This is a visual data mapping tool that can be used by the user to change the data format from one form to another.
3. StyleVision : This application allows the user to create the XSLT and XSL:FO stylesheets which can be used to transform the xml documents. It can also be used to change the xml document into a HTML or PDF file.